Interaction between ω-6 fatty acids intake and blood cadmium on the risk of low cognitive performance in older adults from National Health and Nutrition Examination Survey (NHANES) 2011-2014

Background: Identifying preventable diets and environmental exposure is essential to ensuring the health of the aging population. This study evaluated the interaction effect between blood cadmium and omega-6 fatty acids intake on low cognitive performance in Americans. Method: The data of this cross-sectional study were obtained from the 2011-2012 and 2013-2014 National Health and Nutritional Examination Survey (NHANES). Cognitive performance was measured by the Consortium to Establish a Registry for Alzheimer's Disease test, Animal Fluency Test, and Digit Symbol Substitution Test. Multivariate logistic regression models were used. Results: A total of 1,918 individuals were included, with 467 (24.35%) low cognitive performance. Compared with participants with normal-level blood cadmium, those with high-level blood cadmium had a higher risk of low cognitive performance [odds ratio (OR) was 1.558 with 95% confidence interval (CD: 1.144-2.123]. Low-level omega-6 fatty acids intake was positively associated with low cognitive performance [OR= 1.633 (95%Cl: 1.094-2.436)] compared with normal-level intake. Moreover, there was a significant interaction between low-level omega-6 fatty acids intake and high-level blood cadmium on the risk of low cognitive performance (relative excess risk due to interaction: 0.570, 95%G: 0.208-0.932; the attributable proportion of interaction: 0.219, 95%CI: 0.102-0.336; synergy index: 1.552, 95%CI: 1.189-2.027). Conclusions: There was a synergistic interaction between low-level omega-6 fatty acids intake and high-level blood cadmium on low cognitive performance. Low-level omega-6 fatty acids intake may amplify the adverse effects of long-term exposure to cadmium on cognitive performance. This may have a certain significance for the prevention of cognitive decline in the elderly.

Automated summary

This study evaluated the interaction effect between blood cadmium and omega-6 fatty acids intake on low cognitive performance in Americans, and found that low-level omega-6 fatty acids intake may amplify the adverse effects of high-level blood cadmium on cognitive performance.